The polished table gleams with Kings pattern silver cutlery and beautiful crystal glass with the EIIR cypher. Hostess or not, the Queen is still the monarch, and when the food starts to come around the table on magnificent salvers, she is served first. There are two pages serving, and both start in the middle and work their way round. The Queen prefers to help herself to food, and so the pages who serve hand her the salver on her left side, with a large spoon and fork, and wait while the Queen takes what she wants. She helps herself to a very small portion – the royals eat little and often – and her distinctive voice can be heard after every dish saying ‘thank you’ to the page. This is one of the very rare times when the Queen actually speaks to the staff when they are on duty, and for a new recruit her clipped but courteous ‘thank you’ can be quite a thrill.

At these ‘Meet the People’ lunches, the staff remain in the room while the guests are eating and clear away any empty plates immediately. On other occasions – when the Queen and Philip are lunching with friends at Balmoral or Sandringham, for example – the empty plates are all cleared at once, and staff go out of the dining room while they are eating. Then the Queen rings when it looks as if everyone is finished.

There is plenty on offer to drink, though people are very cautious about how much they take, not wanting to go over the top in the royal presence. The Queen always serves a chilled white Moselle or a German hock from the bottle at lunchtime – never heavy wines. Some red wine is also offered in a claret jug. The Queen likes red wine very much, but she doesn’t drink it at lunchtime. Prince Philip will usually have a light ale.

Salad is always served with the main course, and the Queen places her plate at an angle if she wants salad, and then the footman brings the crystal salad bowl for her to serve herself. The royals prefer to have plain fruit – such as an apple or a pear – as dessert, which is always offered. The Welsh opera singer Katherine Jenkins, who enjoyed a palace lunch in 2009, admitted she was baffled when she was presented with a fruit platter, a plate and a neat piece of gauze with a bowl of water. She had no idea what she was supposed to do with it: ‘Her Majesty caught my eye, helped me out and showed me what I needed to do: wash the fruit in the bowl and clean it with the gauze.’